Karstification of a rock is the phenomenon whereby this rock is fashioned by the dissolution of carbonates in water. The water infiltrates through interstices of the rock, for example pores or fractures, and this infiltration increases the size of these interstices by virtue of the dissolution of carbonates of the rock in the infiltrated water. Fractures and cavities can thus be formed.
The water may typically be rainwater made acid by carbon dioxide from the atmosphere or the ground. The water may, among other things, originate for example from hydrothermal lifts.
The rock may, for example, comprise limestone.
It is known practice to model a karstic region statically, by using observations, in particular geological and seismic observations. When drilling a well, data measured via the well, called well data, can be used to make a posteriori adjustments to the model of the karstic region. However, this traditional approach is limited in that it does not dynamically reproduce the geological and hydrological processes leading to the formation of the karst, and in that the adjustment of the model to the well data can be relatively complex and sometimes unstable.
The article by O. Jaquet et al., “Stochastic discrete model of karstic networks”, Advances in Water Resources 27 (2004), 751-760, describes a method for simulating karstification phenomena based on a stochastic approach. A karstic region is modeled as a network of pipes corresponding to fractures that are more or less wide depending on the diameter of the pipe. Particles corresponding to water droplets are introduced, and their displacement over the network is subjected to laws of “random walk” type.
There is a need to improve the quality of the simulation.